2011 Round 23 Results: Bird Eats Cat

It's a fraught time of year to be wagering on teams whose places in the finals have largely been determined and I can't but help feel Investors were bitten by this reality over the weekend with the Cats maybe 1% off their game and consequently going down to a determined Swans team playing finals footy, and the Dons doing just enough to beat Port Adelaide but nowhere near enough to cover a 70.5 points spread.

Those two unfavourable results, combined with the Crows' poor second-half performance against the Tigers, dug the hole that spread-covering wins by the Hawks and the Saints couldn't fill. Portfolios thus fell by another 6.5c, the third loss in as many rounds, to leave them down now by almost 15c on the season.

That leaves quite a bit of work to do over the remaining 17 games of the season.

Across the round six favourites were victorious, the Cats and the Crows the two exceptions, which helped boost the average Head-to-Head Tipster performance to near season-average levels. This week's average of 5.9 from 8 was the 12th-highest this season.

Best performances came from Consult the Ladder, Silhouette and Short-Term Memory I, which all registered 7 from 8, and the worst performance was Easily Impressed I's 4 from 8.

BKB and Bookie_9 remain locked in leadership of the Head-to-Head Tipsters with just one home-and-away round to go, now on 136.5 from 179 (76.3%) and still just one tip ahead of Combo_NN_1 and Combo_NN_2 on 135.5 from 179 (75.7%). 

Our Margin Predictors also collectively produced approximately season-average performances, turning in a 33.17 MAPE per game for the round, the 13th-best average this season. Best MAPE for the round was Win_7's 28.73 points per game, narrowly bettering Win_3's 28.74 points per game. These were the only Margin Predictors to break 30 this week.

Amongst the leading Margin Predictors Bookie_9 fared best in registering 31.55 points per game, ahead of Combo_NN_2's 32.84, Bookie_3's 34.13, Combo_7's 34.52, and Combo_NN_1's 34.87 points per game. These results leave Bookie_3 atop the MAFL leaderboard on 29.37 points per game, Combo_7 in second on 30.23, and Bookie_9 in third on 30.68 points per game.

Despite the relative mediocrity of their MAPEs, Margin Predictors' line betting predictions were more accurate than usual this week. The average score of 5.2 from 8 was the third-highest average this season, and better-than-chance results for ProPred_3 and ProPred_7 were enough to drag their season averages above the 52.6% rate required for profitability. They now join Bookie_3 as the only Margin Predictors that have tipped at a rate sufficient to have generated profit on line betting had their predictions been followed for each game.

The TAB Sportsbet bookmaker and WinPred were the only Head-to-Head Probability Predictors to produce positive probability scores this week - in WinPred's case by the barest of margins - while ProPred and the H2H Predictors produced negative probability scores. These differential performances were not sufficient to change the overall season-long rankings however.

The Line Fund algorithm produced a very slightly negative probability score.